surface are not repairable and must be replaced.
L e a k s in the return bends and header tubes may in
most cases be repaired by brazing open joints or
specified and in paragraphs 5-25 and 5-26
replacement of return bends.
Refrigerant system must be discharged
reverse order of removal. Upon completion of
before opening the refrigerant system
installation evacuate and re-charge the system
(para 5-8 b ) .
6-11. Repair or Replacement
Coils with internal leaks in tubes in the finned
S e c t i o n IV. CASING ASSEMBLY REPAIR
solvent. Federal Specification P-S-661, wipe both
the inside and outside of the casing, grilles and
The casing assembly is an integral unit except for
gasketing and . insulation. These items may be
replaced if damaged or loose.
Inspect the casing for loose rivets, weldments,
dents. cracks and damaged finish.
a. R e m o v e a n y p a n e l s o r g r i l l e s a t t a c h e d w i t h
screws. Do not attempt to disassemble or separate
6-17. Repair and Replacement
panels or frames that are secured with rivets.
a. Small dents in the casing or panels may be
b. If a case assembly is to be discharged be sure
s t r a i g h t e n e d . Loose rivets should be drilled out and
that all components are removed. Procedures for
replaced and broken welds should be rewelded.
r e m o v i n g all items are contained in chapters 4 and
b. I f t h e c a s i n g i s e x c e s s i v e l y d a m a g e d , i t m u s t
5 of this manual.
c. A n y f i n i s h m i s s i n g f r o m t h e c a s i n g m u s t b e
retouched or the whole casing assembly refinished.
a. Remove scales, loose paint and corrosion with
d. R e p l a c e w e t , d i r t y o r d a m a g e d i n s u l a t i o n .
a wire brush.
b. B l o w l o o s e d i r t f r o m s e a m s a n d c o r n e r s w i t h
c. Use a light air blast to blow dust and dirt from
d. Using a cloth dampened in a dry cleaning